Several police reports have been lodged against two fitness studios whose outlets have allegedly closed down overnight.
Kyklos Studio and its affiliated brand X Fitness are run by Mr Atlas Ang, 31. Their websites and social media pages were suddenly locked or taken down earlier this week, and Mr Ang has become uncontactable.
Attempts by The Straits Times to contact him for comment have also been unsuccessful.
Several users, who told ST that they bought packages ranging from about $200 to $600, are worried that they will not be able to get their money back.
Speaking on condition of anonymity, several said they took up the packages as the studios appeared proper and had outlets in malls.
One woman spent about $300 in August on a package of 20 classes after attending a trial class.
"I have signed packages with other studios and this has never happened before," she added.
"I'm really upset over the fact that they did not even announce anything on their social media and simply disappeared."
She said she had yet to attend a single class and found out about the latest turn of events from a friend on Tuesday (Sept 13).
Her friend tried attending a class she had signed up for, but found that the studio was locked.
Freelance instructors at the studio have also been unable to contact Mr Ang.
The studios are in GR.iD mall in Dhoby Ghaut and Tekka Place in Serangoon.
The X Fitness website, which is no longer available, also lists classes in Hougang Sports Hall.
The police confirmed that several reports had been lodged and are looking into the matter.
Business records show that Mr Ang is the director of four businesses dealing in training courses for sports and games.
They are ACSG 1, Kyklos, X+ and XSC 1.
Kyklos and ACSG 1 appear to be registered to his home address in Punggol, while XSC 1 is registered to the address of the studio in Dhoby Ghaut.
X+ is registered to an address near Chinatown.
He is also listed as the director of Hong Creatives, an advertising outfit, where a man who answered the phone said only that Mr Ang "would be back soon".
This article was first published in The Straits Times. Permission required for reproduction.